PM60163: DFHSO0126 AN ATTEMPT TO CREATE A SOCKET HAS FAILED BECAUSE THE MAXSOCKETS LIMIT HAS BEEN REACHED.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You will see DFHSO0126 W An attempt to create a socket has
  failed because the MAXSOCKETS limit has been reached.
    All the sockets are in use even though all of the send and
  receive sessions have a free status.
    IPCONN does a CLOSE SOCKET and closes the SOCKET in TCPIP yet
  it does not delete the IPIC OUTBOUND SOCKETS.  Nor does it
  delete the INBOUND SOCKETS.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: DFHSO0126 An attempt to create a socket *
  *                      has failed because the MAXSOCKETS       *
  *                      limit has been reached.                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
    A CEMT SET IPCONN RELEASE command is issued.  As part of the
  release processing CICS must close the outbound sockets owned
  by the associated IPCONN.
  
    The close processing determines that there is an outstanding
  asynchronous receive for this socket. The receive is cancelled
  but the socket control block in CICS is not freemained as it
  may still need to be referenced by the sockets notify routine
  which runs when the asynchronous receive completes. The socket
  is then closed and other associated data buffers are freed.
  
    The socket gets added to a delete chain which is managed by
  CSOL. CSOL will freemain the socket block when the asynchronous
  receive completes. Due to the close of the socket being
  issued immediately after the cancel of the receive, CICS
  is never notified that the receive was cancelled.
  
    The socket block now remains in CICS and will never be
  deleted and is also taking up 1 socket towards the CICS
  MAXSOCKETS count.
  
    If IPCONNs are released enough times eventually CICS will
  reach the MAXSOCKETS limit.
  

Problem conclusion

• CICS Sockets domain has been changed to ensure that the socket
  block gets freed whenever a CEMT SET IPCONN RELEASE completes.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  PM56428

• APAR is sysrouted TO one or more of the following:

  UK79360

Modules/Macros

•    DFHSOAD  DFHSOCK  DFHSODM  DFHSODUF DFHSOIS
  DFHSOL   DFHSOLI  DFHSOLS  DFHSOLX  DFHSOM01 DFHSOM02 DFHSOM03
  DFHSOPL  DFHSORD  DFHSOSE  DFHSOST  DFHSOS00 DFHSOS01 DFHSOS02
  DFHSOS03 DFHSOS04 DFHSOS05 DFHSOS06 DFHSOS07 DFHSOS08 DFHSOS09
  DFHSOS10 DFHSOS11 DFHSOS12 DFHSOS13 DFHSOS14 DFHSOS15 DFHSOS16
  DFHSOS17 DFHSOS18 DFHSOS19 DFHSOS20 DFHSOS21 DFHSOS22 DFHSOS23
  DFHSOTB  DFHSOTI  DFHSOTRI DFHSOUE  DFHSOXM
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R700 PSY UK79360

     UP12/06/15 P F206

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.